Bush's Concept 

Vannevar Bush thought the system libraries used for cataloging and storing information was not a natural method for people to follow because it is based on an artificial system of indexing. What makes it difficult to locate the information is the alphabetic and numeric filing system that forces the researcher to look from subclass to subclass. To appropriately use such a system requires that one know a set of cumbersome rules to locate the information.

Bush developed his concept using a trail as an analogy with the human brain. In his article, As We May Think, Bush indicated "the human mind operates by association. With one item in its grasp, it snaps instantly to the next that is suggested by the association of thoughts, in accordance with some intricate web of trails carried by the cells of the brain" (Bush 6). It was on this concept that Bush envisioned his theoretical Memex machine.